Las Vegas residents line up to donate blood after shooting

LAS VEGAS -- People are lining up to donate blood in Las Vegas following the deadliest mass shooting in modern U.S. history.

Photos posted on social media show groups of people waiting in line to get into the United Blood Services.

According to Access Vegas, some arrived even before the doors opened.

"People already lined up at United Blood Services to donate blood. 7930 W. Charleston," they tweeted.

Once the doors opened, the line continued to grow.

"The line to donate blood is out the door at United Blood Service. People have been here all night waiting for it to open," KTNV reporter Yasmeen Hassan tweeted.

Once inside the United Blood Services building, people waited their turn to donate blood.

"#VegasStrong out in force to support those in need after the horrific action last night! Come out and help anyway you can. #DonateBlood," Michael Su tweeted.

Shanda Maloney tweeted photos of the donors saying, "Thank you #Vegas for coming together."

The Las Vegas Metropolitan Police Department is telling those who would like to donate blood to the injured to visit the Labor Health & Welfare Clinic.

Police say 64-year-old Stephen Paddock killed at least 50 people and wounded more than 200 in a shooting during an outdoor country music festival. Paddock died at the scene.